From 3ce167123a6059e174047d4580edce56c5019fb9 Mon Sep 17 00:00:00 2001
From: Mathieu Maret <mathieu.maret@gmail.com>
Date: Thu, 12 Jul 2018 14:07:24 +0200
Subject: [PATCH] Add way to print int

---
 vga.c | 33 ++++++++++++++++++++++++++-------
 vga.h |  8 +++++---
 2 files changed, 31 insertions(+), 10 deletions(-)

diff --git a/vga.c b/vga.c
index 0925e02..0dd48be 100644
--- a/vga.c
+++ b/vga.c
@@ -1,6 +1,6 @@
 #include "vga.h"
 
-void clearScreen(int bgColor)
+void clearScreen(uint bgColor)
 {
 	volatile short *vga = (short *)VGA_ADDR;
 	long int colorAttr  = bgColor << 12;
@@ -9,18 +9,37 @@ void clearScreen(int bgColor)
 	}
 }
 
-void printChar(const char str, int color, int bgColor, int startX, int startY)
+void printInt(int integer, uint color, uint bgColor, int startX, int startY)
 {
-	volatile short *vga	   = (short *)VGA_ADDR;
-	long int colorAttr	    = (bgColor << 4 | (color & 0x0f)) << 8;
+	char num[sizeof(int) *
+		 3]; // int max is 2^(sizeof(int)*8) which is (2^3)^(sizeof(int)*8/3) =
+		     // 8^(sizeof(int)*8/3) ~ 10^(sizeof(int)*8/3)
+	int x = startX;
+	int i = 0, k = 0;
+	if (integer < 0) {
+		printChar('-', color, bgColor, x++, startY);
+		integer = -integer;
+	}
+	while (integer != 0) {
+		num[i++] = integer % 10;
+		integer  = integer / 10;
+	}
+	for (k = i - 1; k >= 0; k--) {
+		printChar(num[k] + '0', color, bgColor, x++, startY);
+	}
+}
+
+void printChar(const char str, uint color, uint bgColor, int startX, int startY)
+{
+	volatile short *vga       = (short *)VGA_ADDR;
+	long int colorAttr        = (bgColor << 4 | (color & 0x0f)) << 8;
 	vga[80 * startY + startX] = colorAttr | str;
 }
 
-void printString(const char *str, int color, int bgColor, int startX,
-		 int startY)
+void printString(const char *str, uint color, uint bgColor, int startX, int startY)
 {
 	volatile short *vga = (short *)VGA_ADDR;
-	int i		    = 0;
+	int i               = 0;
 	long int colorAttr  = (bgColor << 4 | (color & 0x0f)) << 8;
 	while (*str) {
 		vga[80 * startY + startX + i] = colorAttr | *str;
diff --git a/vga.h b/vga.h
index d32d6a3..e426fb9 100644
--- a/vga.h
+++ b/vga.h
@@ -1,4 +1,5 @@
 #pragma once
+#include "types.h"
 
 #define BLACK   0x00
 #define BLUE    0x01
@@ -14,6 +15,7 @@
 #define VGA_WIDTH  80
 #define VGA_HEIGHT 15
 
-void clearScreen(int bgColor);
-void printChar(const char str, int color, int bgColor, int startX, int startY);
-void printString(const char *str, int color, int bgColor, int startX, int startY);
+void clearScreen(uint bgColor);
+void printInt(int integer, uint color, uint bgColor, int startX, int startY);
+void printChar(char str, uint color, uint bgColor, int startX, int startY);
+void printString(const char *str, uint color, uint bgColor, int startX, int startY);